Maxwell Technologies ultra-capacitor

Maxwell Technologies is marketing an ultra-capacitor that will replace one or two truck batteries and help start a truck. The unit is dry, maintenance-free, saves weight and provides protection against no-starts, the company says. It stores electricity on metal plates rather than through a chemical process used in batteries, making it less sensitive to cold temperatures. Minimal degradation occurs as the temperature drops from 100 degrees to below zero, the company says.

The unit offers less resistance to current flow than a battery, enabling it to crank the engine substantially faster, a benefit in cold starts, the company says. The unit stores enough energy for three potent cranking cycles of about four seconds each.